SWG not working

The cell has an internal water temperature sensor.

Is your heater running?


The LCD display will read “HOT” when the water temperature is above 140 oF.

If the water temperature reads greater than 140F, the cell temperature sensor is shorted and the cell needs to be replaced. It may be a problem with the temperature sensor in the cell or a problem with the circuit board reading the temperature sensor.

If you have a multimeter, you can check the resistance of the thermistor in the cell (pin 6 against pin 10 on the plug). See Temperature Sensors.

Cutting either the Red or Blue wire should get the Temperature display to read 77F.

Some people have patched into the cable and installed an external temperature sensor.

Holding the plug vertically with the cord going down and looking at the connection points. 1 is top left, 2 is top right, 3 is second down left, and so on with 9 being lower left and 10 being lower right.

• 1) Black - Power to cell
• 2) White - Power to cell
• 3) Black - Power to cell
• 4) White - Power to cell
• 5) Brown - Not used
• 6) Red - Goes to thermistor
• 7) Orange - Not used on older models, used for OEM sense on new models.
• 8) Yellow - Not used on older models, used for OEM sense on new models.
• 9) Green - Not used
• 10) Blue - Goes to thermistor.

To test the thermistor test between points 6 and 10 using a multimeter, the resistance should follow a 10k thermistor chart.